The general scope of this project is to study biological properties of human herpesviruses and human papovaviruses tentatively associated with tumors in human patients. At present the following topics are under investigation. 1) Studied on the Fc receptor induced by herpes simplex virus; 2) Characterization of the interaction of a human papovavirus with human cells in vitro. BIBLIOGRAPHIC REFERENCES: Costa, J., Yee, C., Tralka, T.S., and Rabson, A. S.: Hamster ependymomas produced by intracerebral inoculation of a human papovavirus. J. Natl. Cancer Inst. 56: 104-105, 1976. Costa, J.C., Howley, P.M., Legallais, F.Y., Yee, C.L., Young, N.A., and Rabson, A.S.: Oncogenicity of a nude mouse cell line transformed by a human papovavirus. J. Natl. Cancer Inst. 58: 1147-1150, 1977.